_Thern%25C3%25B6e.png) Shape model of Thernöe from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | L. Oterma |
| Discovery site | Turku Obs. |
| Discovery date | 15 October 1941 |
| Designations | |
| (1545) Thernöe | |
Named after | Karl August Thernöe (Danish astronomer)[2] |
| 1941 UW · 1932 YD 1955 VV · 1957 HY A906 FE · A915 CE | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 111.21 yr (40,619 days) |
| Aphelion | 3.4299AU |
| Perihelion | 2.1097 AU |
| 2.7698 AU | |
| Eccentricity | 0.2383 |
| 4.61yr (1,684 days) | |
| 84.917° | |
| 0° 12m 49.68s / day | |
| Inclination | 2.9542° |
| 51.800° | |
| 90.542° | |
| Physical characteristics | |
| 16.12±5.02 km[4] 17.796±0.210 km[5] 18.656±0.376 km[6] 18.71±1.1 km[7] 19.37±0.31 km[8] | |
| 17.20±0.01 h[9] 17.20321±0.0001 h[10] | |
| 0.092±0.004[8] 0.0962±0.013[7] 0.097±0.012[6] 0.1063±0.0153[5] 0.13±0.10[4] | |
| SMASS =K[1] · C[11] | |
| 11.76[4] · 11.8[11][5][6][7][8] · 11.9[1] · 12.09±0.45[12] | |
1545 Thernöe (provisional designation1941 UW) is an elongatedbackground asteroid from the central region of theasteroid belt. It was discovered on 15 October 1941, by Finnish astronomerLiisi Oterma atTurku Observatory in Southwest Finland.[3] The uncommonK-type asteroid has arotation period of 16.1 hours and measures approximately 18 kilometers (11 miles) in diameter. It was later named after Danish astronomerKarl August Thernöe.[2]
Thernöe orbits the Sun in thecentral main-belt at a distance of 2.1–3.4 AU once every 4 years and 7 months (1,684 days). Its orbit has aneccentricity of 0.24 and aninclination of 3° with respect to theecliptic.[1] It was first identified asA906 FE atHeidelberg Observatory in 1906, extending the body'sobservation arc by 35 years prior to its official discovery observation at Turku.[3]
Thisminor planet was named after Karl August Thernöe (1911–1987), Danish astronomer and celestial mechanic atØstervold Observatory in Copenhagen. He was also a popularizer of astronomy and director ofIAU'sCentral Bureau for Astronomical Telegrams during 1950–1964.[2][13] The officialnaming citation was published by theMinor Planet Center on 20 February 1976 (M.P.C. 3930).[14]
In theSMASS taxonomy, Thernöe is classified as a rareK-type asteroid, a newly introduced subtype that belongs to the broaderS-complex of stony bodies.[1] Conversely, CALL groups Thernöe into the carbonaceousC-complex.[11]
In December 2006, a rotationallightcurve of Thernöe was obtained from photometric observations by French amateur astronomerRené Roy. Lightcurve analysis gave a well-definedrotation period of 17.20 hours with a brightness variation of 0.76magnitude (U=3).[9] The high lightcurve-amplitude of 0.76 indicates that the body has a non-spheroidal shape.
A 2016-published lightcurve, using modeled photometric data from the Lowell Photometric Database, gave a concurring period of 17.20321 hours, as well as aspin axis of (164.0°, −5.0°) inecliptic coordinates (λ, β).[10]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite, and NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission, Thernöe measures between 16.12 and 19.37 kilometers in diameter and its surface has analbedo between 0.092 and 0.13.[4][5][6][7][8] TheCollaborative Asteroid Lightcurve Link (CALL) adopts the results obtained by IRAS, that is, an albedo of 0.0962 and diameter of 18.71 kilometers with anabsolute magnitude of 11.8.[11]
